Motorcycle Chassis Design Digest #721-730

MC-Chassis-Dgst Monday, August 10 1998 Volume 01 : Number 721
1. "Michael Moore" Subj: Re: MC-Chassis- scalloping tube
2. Eugene Shafir <04shafir@cua.edu> Subj: Re: MC-Chassis- scalloping tube
3. "Jim Schneider" Subj: Re: MC-Chassis-Dgst V1 scolloping tube
4. David E Harhay Subj: MC-Chassis lean angle
5. Alan Lapp Subj: Re: MC-Chassis Grit in ATF?
6. "Thomas Alberti" Subj: Re: MC-Chassis lean angle
7. Paul Kellner Subj: Re: MC-Chassis-Dgst V1 scolloping tube
8. "Michael Moore" Subj: Re: MC-Chassis scolloping tube
9. Eugene Shafir <04shafir@cua.edu> Subj: Re: MC-Chassis-Dgst V1 scolloping tube
----------------------------------------------------------------------
Date: Sat, 8 Aug 1998 14:35:37 -0800
From: "Michael Moore"
Subject: Re: MC-Chassis- scalloping tube
> I wrote a small program for creating templates for tube profiling. Both
> executable and source code in BASIC available at
>
> http://www.campus.cua.edu/~04shafir/home.htm
>
> Now, if someone can program printers...
Hello Eugene,
There is a shareware (not freeware) program called WinMiter that
outputs wrap-around templates. I fiddled with it a bit, and it looks
like you may need to request a slightly bigger tube than actually
being used to get the template to fit right.
The program accepts the diameter of the tube to be modified, the tube
diameter to be modified to butt up to, the angle of the joint, and
possibly centerline offset. I haven't looked at it for quite a
while, so I don't recall for sure.
Cheers,
Michael
------------------------------
Date: Sat, 08 Aug 1998 18:56:45 -0400
From: Eugene Shafir <04shafir@cua.edu>
Subject: Re: MC-Chassis- scalloping tube
Michael Moore wrote:
>
>
> There is a shareware (not freeware) program called WinMiter that
> outputs wrap-around templates. I fiddled with it a bit, and it looks
> like you may need to request a slightly bigger tube than actually
> being used to get the template to fit right.
>
Thanks Michael, I found WinMiter at:
http://members.aol.com/jketterer/winmiter.exe
Looks like that's what I tried to do.
Eugene Shafir
------------------------------
Date: Sat, 8 Aug 1998 19:00:56 -0600
From: "Jim Schneider"
Subject: Re: MC-Chassis-Dgst V1 scolloping tube
Accessed this site and didn't get anything to open??? Error in address?
Jim
Swiss
- -----Original Message-----
From: Eugene Shafir <04shafir@cua.edu>
To: mc-chassis-design@list.sirius.com
Date: Saturday, August 08, 1998 2:22 PM
Subject: Re: MC-Chassis-Dgst V1 scolloping tube
>Calvin Grandy wrote:
>>
>> Now, we also had a mathematician in our group. He was a quite
guy,
>> that did much of the electrical design for some of the real spiffy
>> stuff that goes into high end toys. He put his thinking cap on, and
>> like a good HVAC duct work mechanic, laid out the shape of each
>> required intersection on a sheet of Molar, complete with a reference
>> line for length and "rotation". These layouts were cut out to provide
>> a full scale profile of the required tube end .
>
>
>I wrote a small program for creating templates for tube profiling. Both
>executable and source code in BASIC available at
>
>http://www.campus.cua.edu/~04shafir/home.htm
>
>Now, if someone can program printers...
>
>
>Eugene Shafir
------------------------------
Date: Sun, 9 Aug 1998 09:47:18 -0400
From: David E Harhay
Subject: MC-Chassis lean angle
Sorry for the double posts. I dug through the file cabinet and found
this thing: The 'g-curve' (no puns now!!) dubbed a simple vehicle
accelerometer. It is an inverted protractor with a curved glass tube
that has a ball inside. Suction cups hold it to a mount (window), the
ball indicates the acceleration, which is read from the adjacent scale.
The literature states is good for cornering, braking, and launching.
Analytical Performance, 3104 E Camelback Rd, Suite 528, Phoenix,
AZ, USA,Fax 602-953-2229. A modification on this is the similar
inverted protractor with a pointer pivoting on bearings with a one
way clutch attathed to the opposite of the pointer. This would allow
the lean angle to be obtained by the rider and no cameras, etc.
Just 'zero' it first and go, your max lean angle would be on the scale
until the device was reset.
Another interesting device is the Ram Jett Performance Computer.
It was showcased in Dealernews 4/91. Strap it on to your machine
with bungee cords and go! Measures HP and torque and maybe
acceleration. Ram Jett, POB 1521, Santa Maria, CA, 93456, 805-
934-5833.
Both of these may not be around anymore. Just wanted to share the
thoughts.
Dave Harhay
------------------------------
Date: Sun, 9 Aug 1998 10:17:04 +0100
From: Alan Lapp
Subject: Re: MC-Chassis Grit in ATF?
>I am about to replace the fork oil on one of my
>bikes. I like to use ATF but read recently that
>either Dexron or type F automatic trans fluid has
>"grit" as an ingredient. Is this true? If so,
>which type has it? I've been using Dexron...
>
>Thanks!
>
>Jon Hose
>
>(P.S. I assume that grit is some kind of friction
>enhancing rather than reducing material)
Actually, the grit is an anti-foaming agent. There is a similar situation
with some automotive anti-freeze products. Honda Gold Wings are often
mentioned as very susceptible to water pump seal failures when using
improper anti-freeze.
Al
level_5_ltd@earthlink.net
------------------------------
Date: Sun, 9 Aug 1998 09:48:43 -0500
From: "Thomas Alberti"
Subject: Re: MC-Chassis lean angle
> AZ, USA,Fax 602-953-2229. A modification on this is the similar
> inverted protractor with a pointer pivoting on bearings with a one
> way clutch attathed to the opposite of the pointer. This would allow
> the lean angle to be obtained by the rider and no cameras, etc.
> Just 'zero' it first and go, your max lean angle would be on the scale
> until the device was reset.
I think that you are mistaken. This device will show lean angle only at
rest (as you tip the bike back and forth in the pits). During a turn, the
device will essentially point at zero, as the force of gravity will be
balanced by the centrifugal force on the pointer.
It reminds me of flying: during a turn (bank), you can dangle the
microphone from its cord, it will hang straight "down", which means
directly towards the floor of the plane, but not straight towards the
earth. (That is, if you are making a coordinated turn).
Thomas
------------------------------
Date: Sun, 9 Aug 1998 14:56:39 -0400
From: Paul Kellner
Subject: Re: MC-Chassis-Dgst V1 scolloping tube
Eugene wrote:
>I wrote a small program for creating templates for tube profiling. Both
>executable and source code in BASIC available at
>http://www.campus.cua.edu/~04shafir/home.htm
>Now, if someone can program printers...
I have no clue how to program printers, but try the following Lisp-routine
with any old version of Autocad, it draws tube-templates of any diamtr. and
under any angle, simply print/plot the template at 1:1 scale.
In- and output is metric (mm); the template is drawn at 15 degr. intervals
along the tube-circumfence, change the numbers accordingly for more
accuracy.
Copy and paste the following listing with MS-Notepad, save as "Notch.lsp"
Hope I didn't make any big errors in the maths, feel free to replace any
clumsy program lines for your own!
Paul
;Autocad lisp-routine for notched tube templates
;Copy to working directory as "NOTCH.LSP": start new dwg,
;command: (load"notch")
;command: tee
;Tube1 is the notched tube, Tube2 is the main tube (>= Tube1)
;Angle is included angle between tube1 and tube2 (<=90)
(defun c:tee ()
(setq D1 (/ (getreal "\nDiameter Tube1: ") 2))
(setq D2 (/ (getreal "\nDiameter Tube2: ") 2))
(while (< D2 D1)
(setq D2 (/ (getreal "\nDiameter Tube1 must be < diameter Tube2: ") 2))
)
(setq BETA (getangle "\nAngle tube1-tube2 <=90: "))
(while (> BETA (/ 90 (/ 180 pi)))
(setq BETA (getangle "\nAngle must be <= 90 degrees: "))
)
(setq C (/ (* pi (* 2 D1)) 24))
(setq B 0)
(setq A 0)
(setq X (/ 15 (/ 180 pi)))
(setq P1 "0,0")
(repeat 25
(setq PA (* (/ B C) C))
(setq E (/ (- D1 (* D1 (cos A))) (/ (sin BETA) (cos BETA))))
(setq Q (/ (sqrt (- (* D2 D2) (expt (* (sin A) D1) 2))) (sin BETA)))
(setq T (/ D2 (sin BETA)))
(setq PB (+ E (- T Q)))
(setq P2 (list PA PB))
(Command "LINE" P1 P2 "")
(Command)
(setq P1 (list (car P2) (cadr P2)))
(setq B (+ B C))
(setq A (+ A X))
)
)
------------------------------
Date: Sun, 9 Aug 1998 12:04:43 -0800
From: "Michael Moore"
Subject: Re: MC-Chassis scolloping tube
> I have no clue how to program printers, but try the following Lisp-routine
> with any old version of Autocad, it draws tube-templates of any diamtr. and
> under any angle, simply print/plot the template at 1:1 scale.
> In- and output is metric (mm); the template is drawn at 15 degr. intervals
> along the tube-circumfence, change the numbers accordingly for more
> accuracy.
Hello Paul,
does the LISP routine presume common centerlines for the tubes?
Cheers,
Michael
------------------------------
Date: Mon, 10 Aug 1998 12:46:38 -0400
From: Eugene Shafir <04shafir@cua.edu>
Subject: Re: MC-Chassis-Dgst V1 scolloping tube
Jim Schneider wrote:
>
> Accessed this site and didn't get anything to open??? Error in address?
>
Hello Jim,
I removed all the files, after Michael pointed me at WinMiter program.
Now they are back.
Eugene
------------------------------
End of MC-Chassis-Dgst V1 #721
******************************
MC-Chassis-Dgst Tuesday, August 11 1998 Volume 01 : Number 722
1. Paul Kellner Subj: Re: MC-Chassis scolloping tube
2. Nedragr345@aol.com Subj: Re: MC-Chassis Non-Topic: Honda Part Needed
3. info2@cashprofits.net Subj: MC-Chassis CREDIT CARD PROCESSING
4. "Max Hall" Subj: MC-Chassis Remove
5. "Thomas Alberti" Subj: Re: MC-Chassis Non-Topic: Honda Part Needed
6. "Michael Moore" Subj: MC-Chassis Romanelli FFE
----------------------------------------------------------------------
Date: Mon, 10 Aug 1998 14:16:43 -0400
From: Paul Kellner
Subject: Re: MC-Chassis scolloping tube
>does the LISP routine presume common centerlines for the tubes?
>Cheers,
>Michael
Hello Michael,
yes, it doesn't allow for any offset, you'd have to change the maths for
the "Y-component" to do that, these are the E,Q and T variables.
Paul
------------------------------
Date: Mon, 10 Aug 1998 22:01:31 EDT
From: Nedragr345@aol.com
Subject: Re: MC-Chassis Non-Topic: Honda Part Needed
Hey Thomas, I'll give you $500 for it as is... :)
------------------------------
------------------------------
Date: Tue, 11 Aug 1998 07:24:37 -0500
From: "Thomas Alberti"
Subject: Re: MC-Chassis Non-Topic: Honda Part Needed
> Hey Thomas, I'll give you $500 for it as is... :)
Chris, you are a sick man.
Thomas
------------------------------
Date: Tue, 11 Aug 1998 19:48:37 -0800
From: "Michael Moore"
Subject: MC-Chassis Romanelli FFE
The 10/98 issue of "Sport Rider" came today, and included an article
on the Ducati with FFE designed by Franco Romanelli (they featured
the 6 valve cylinder heads designed by FR in an earlier article, with
just a teaser photo of the FFE).
It looks to me the FFE is a Difazio/Tait/Bimota HCS with the lower
arm moved up about 5 or 6 inches, a non-pivoting U-shaped upright
that carries the stationary axle mounted to the two sets of arms, and
the pivoting upright supported by the kingpin bearing and a bearing
at the top of the stationary upright.
His design does have some advantages over those with a front
swingarm mounted near the axle level: potentially shorter wheelbase
(no pivot assy between the back of the tire and the front of the
engine/chassis) and no ground clearance problems when at maximum
lean (though this can be dealt with in the others by careful design).
The writer mentioned the lack of rearward bending in the FFE. The
front end may not noticably bend back, but that isn't helped any by
the arrangement of the lower tie rods which cause the upright to be
loaded in bending during braking. The short, large section upright
just won't bend very much when compared to a smaller section and
longer tele-fork.
I'm not sure I see any big improvements overall, but it was
interesting to see the design.
Cheers,
Michael
------------------------------
End of MC-Chassis-Dgst V1 #722
******************************
MC-Chassis-Dgst Thursday, August 13 1998 Volume 01 : Number 723
1. "Joe Allan" Subj: MC-Chassis REMOVE
2. "Michael Moore" Subj: Re: MC-Chassis REMOVE spamola message from the list admin
3. "Thacker, Heath HW" Subj: MC-Chassis Tyre Loading & Lean angle Clearance.
4. "Joe Allan" Subj: Re: MC-Chassis REMOVE
5. batwings@i-plus.net Subj: Re: MC-Chassis Tyre Loading & Lean angle Clearance.
6. "Michael Moore" Subj: MC-Chassis List T-shirt votes - first call
7. "Thacker, Heath HW" Subj: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
----------------------------------------------------------------------
------------------------------
Date: Tue, 11 Aug 1998 21:13:08 -0800
From: "Michael Moore"
Subject: Re: MC-Chassis REMOVE spamola message from the list admin
Sending a remove message back to the list does nothing except fill
the mailboxes of everyone on the list with another message to delete,
especially if you include the original spam message.
Even if you respond to the spammers, all it does is let them know
they got a good address.
Hey, they're SPAMMERS after all, so why would you believe they'd
really stop sending spam once they've determined they've got a good
address.
I had set the list to accept outside posts while I was out of town
because some people new to the list were having troubles with getting
the list to ID their addresses. Now that the list has received spam,
I'll be setting it back to reject any address not on the subscriber
list, so if anyone has problems let me know.
Cheers,
Michael
------------------------------
Date: Wed, 12 Aug 1998 14:12:01 +1000
From: "Thacker, Heath HW"
Subject: MC-Chassis Tyre Loading & Lean angle Clearance.
G'Day mc-chassis-design listers,
I've been in lurk mode on this list for some time now (3 months or so).
I (almost) got sent here from the GSXR list, as my questions were too
much of a techical nature. Although, they are still well below the
level of this list.
Quick intro, My name is Heath, and I own an '88 GSXR750J. Stage 1
Dynojet kit, & 4into1 exhaust. Significant flat spot in midrange, so I
starting to learn about exhaust design & sound waves, savaging, & all
that good stuff.
If its OK to ask exhaust or engine design questions here, I'll probably
have more to follow.
But todays question is regarding tyre loading & clearance. My '88 GSXR
lack lean angle ground clearance. Stock suspension was too soft, so I
replaced the fork springs for progressive ones, and the rear shock for a
works performance unit. Sag set at 1-2inches. I've also remounted my
exhaust can about 1 inch higher. I've also removed my fairing lowers as
these scrap too. Still ground clearance is too low, side stand on one
side * exhaust on the other side, scrap easily. (And I'm no gun racer,
just a street rider who enjoys track days)
As a final attempt, I've slide my forks way down in the tripple clamp,
which (as expected) has slowed steering (no major problem with a
Battleaxe BT58R on the front (steering still quite respectable). Now it
scapes out further towards the back. Any suggestions on how to get more
lean angle clearance would be appriecated.
However, my major concern is the effect this will have on
oversteer/understeer charateristics. By moving the tripple clamps up, &
putting less weight on the front end, have I reduced the bikes tendency
to oversteer. I'm particularly concerned as I've just picked up a
Dunlop 207GP rear (exraced, almost new, very cheap). This tyre has more
grip than my front (exrace, BT58R). Am I a front end side just waiting
to happen ? Is there anything I can do to help ?
Sorry if this is too far off topic.
Heath.
'88 GSXR750J
'95 YZ125G
------------------------------
Date: Wed, 12 Aug 1998 06:57:10
From: batwings@i-plus.net
Subject: Re: MC-Chassis Tyre Loading & Lean angle Clearance.
At 02:12 PM 8/12/98 +1000, you wrote:
>But todays question is regarding tyre loading & clearance. My '88 GSXR
>lack lean angle ground clearance. Stock suspension was too soft, so I
>replaced the fork springs for progressive ones, and the rear shock for a
>works performance unit. Sag set at 1-2inches.
Set your sag to less. Looks to me as if you have another inch or two there.
Ditto front fork. Sag isn't nearly as critical on asphalt bikes as on dirt
bikes.
Sounds to me as if you should be RRing the beast though, if you get over
that far on the street.
>By moving the tripple clamps up, &
>putting less weight on the front end, have I reduced the bikes tendency
>to oversteer.
Move yer body around a bit to compensate. Raising the forks can't shift
things but an inch or so at most.
Best wishes,
Hoyt
------------------------------
Date: Wed, 12 Aug 1998 16:21:04 -0800
From: "Michael Moore"
Subject: MC-Chassis List T-shirt votes - first call
It doesn't look like anymore designs are going to come in, so it is
now time to take a vote on which T-shirt to have printed first.
Check out the different designs at the bottom of:
http://www.eurospares.com/graphics.htm
The designer of the shirt that is picked for printing (and I
anticipate we'll eventually print 2 or 3 of the designs as they are
all quite nice) will get their shirt for free, as well as all the
glory they can grab. I'm hoping the shirts will be about US$15
each, or a bit less, plus postage. That will include a dollar or two
per shirt to go to the running-the-list fund. I'd also like to to
have the price on the shirt set to subsidize (in the spirit of list
camaraderie) to some degree the postage for those people on the list
who are outside the U.S.A..
Shirts will be pocket-less Hanes Beefy-T or better in quality. I
loathe cheap T-shirts.
************************************
How the voting will be conducted:
The names of the designers are:
Ben Bennett
Bruce Brown
Jon Hose
Paul Kellner
Jeff Rozycki
Please rank all the designs from 1 (highest) to 5 (lowest). Indicate
next to each name how many shirts of each design you would anticipate
wanting (remembering that only one design will be printed at first,
so you won't be needing to pony up for 5 times X number of shirts at
once), what color shirt you think the design would look best printed
on (or at least a general white vs colored indication), and the size
shirt you'd want.
So a sample ballot might be:
1Ben Bennett 3 white XL, XL, Small
2 Bruce Brown 3 white XL
3 Jon Hose 3 yellow XL
4 Paul Kellner 3 colored XL
5 Jeff Rozycki 3 white XL
Something along those lines would have Ben's shirt being printed
first, with decreasing priority down to Jeff's design (and keep in
mind this is just an example your ballot may vary, always wear a
helmet, preserve nature, . . .)
By ranking all the designs I should be able to get a good feel for
the next shirt to be printed in a hopefully long series of stunning
designer wear. I'll also need the color/size (I think colors and
XXL shirts are a bit more expensive) number info for getting a quote
on the shirts.
There is a person in the screen printing trade on one of the lists,
and I'm going to give him first crack at the job, as well as badger
him for constructive tips etc.
PLEASE DON'T SEND THE RESPONSE TO THE LIST.
You can send it to me direct at:
mmoore@eurospares.com
I'll re-issue this message as a reminder in about a week, and as soon
as the messages stop trickling in I'll compile the results and
present them to all the lists.
Thanks,
Michael
------------------------------
Date: Thu, 13 Aug 1998 16:01:04 +1000
From: "Thacker, Heath HW"
Subject: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
> From: batwings@i-plus.net[SMTP:batwings@i-plus.net]
>
> Set your sag to less. Looks to me as if you have another inch or two
> there.
> Ditto front fork. Sag isn't nearly as critical on asphalt bikes as on
> dirt
> bikes.
>
On the rear say is currently about 1 inch. I was told if I reduced any
further, I'd be increasing the change of highsiding, as the suspension
would be topped out.
> Sounds to me as if you should be RRing the beast though, if you get
> over
> that far on the street.
>
Thanks, and I'd love too, but in a race you'ld get pretty sick of
passing the newer more powerful bikes in the corners only to be eaten up
down the straights. I've done this on a few practice days, the new T
model SRAD GSXR's are just too powerful in a straight line for this old
'88 model. And I don't have the $ to upgrade much.
> >By moving the tripple clamps up, &
> >putting less weight on the front end, have I reduced the bikes
> tendency
> >to oversteer.
>
> Move yer body around a bit to compensate. Raising the forks can't
> shift
> things but an inch or so at most.
>
On the GSXR my weight is pretty much as far forward as it can be I
think.
Thanks for dampening my fears. My next track day is next weekend, so
I'll ride with less concern about the front end sliding out.
Heath.
------------------------------
End of MC-Chassis-Dgst V1 #723
******************************
MC-Chassis-Dgst Thursday, August 13 1998 Volume 01 : Number 724
1. "Stewart Roger Milton" Subj: MC-Chassis Measuring lean angle etc.
2. batwings@i-plus.net Subj: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
3. Andy Overstreet Subj: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
4. yhakim@m5.sprynet.com Subj: Re: MC-Chassis Measuring lean angle etc.
5. "Thacker, Heath HW" Subj: RE: MC-Chassis Measuring lean angle etc.
6. "Thacker, Heath HW" Subj: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
7. "Thacker, Heath HW" Subj: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
8. "Michael Moore" Subj: MC-Chassis (Fwd) RE: New Member Project
9. "Michael Moore" Subj: MC-Chassis Senor Bulto
----------------------------------------------------------------------
Date: Thu, 13 Aug 1998 12:10:10 +0200
From: "Stewart Roger Milton"
Subject: MC-Chassis Measuring lean angle etc.
At the following site there's an interesting bike designed and used by
Keith Code for teaching leaning to extreme angles and sliding the rear
tyre. The device attached to the bike looks like it could easily be
modified for measuring lean angle, (and maybe stop you highsiding while you
do it!) although the attempt at measurement will change the system your
trying to evaluate!
http://www.motorcycle.com/mo/mccustom/slide.html
The rest of the mag there is pretty good too, although I think Mitch
pointed that out a few days back.
If someone else has pointed this page out already forgive me, I haven't had
any incoming mail for 24 hours or so and haven't seen the latest posts.
Regards,
Stewart Milton
SRM Engineering cc
srmilton@global.co.za or
srm@technologist.com
------------------------------
Date: Thu, 13 Aug 1998 06:38:54
From: batwings@i-plus.net
Subject: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
At 04:01 PM 8/13/98 +1000, you wrote:
>On the rear say is currently about 1 inch. I was told if I reduced any
>further, I'd be increasing the change of highsiding, as the suspension
>would be topped out.
It's your choice; you are bottoming out right now on the ground, no? I
doubt you'll highside it if you raise the seat hgt an inch. I seriously
think whoever told you that hasn't got a clue.
of course the best answer might be stiffer springs.
Let us know how you do next time you ride.
best wishes,
Hoyt
------------------------------
Date: Thu, 13 Aug 1998 06:01:58 -0600 (MDT)
From: Andy Overstreet
Subject: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
On Thu, 13 Aug 1998 batwings@i-plus.net wrote:
> It's your choice; you are bottoming out right now on the ground, no? I
> doubt you'll highside it if you raise the seat hgt an inch. I seriously
> think whoever told you that hasn't got a clue.
>
> of course the best answer might be stiffer springs.
>
> Let us know how you do next time you ride.
>
> best wishes,
>
> Hoyt
Hi, Hoyt - I remember the magazines complaining about this particular
model when it came out. Aren't there different suspension links available
(Or can be made) to raise it? Would this be a good way to go if the spring
is already stiff enough?
Andy Overstreet
------------------------------
Date: Thu, 13 Aug 1998 08:09:30 -0700
From: yhakim@m5.sprynet.com
Subject: Re: MC-Chassis Measuring lean angle etc.
Gary Rothwell rode the slide machine and manged to flip it!
On Thu, 13 Aug 1998, "Stewart Roger Milton" wrote:
>At the following site there's an interesting bike designed and used by
>Keith Code for teaching leaning to extreme angles and sliding the rear
>tyre. The device attached to the bike looks like it could easily be
>modified for measuring lean angle, (and maybe stop you highsiding while you
>do it!) although the attempt at measurement will change the system your
>trying to evaluate!
>
>http://www.motorcycle.com/mo/mccustom/slide.html
>
>The rest of the mag there is pretty good too, although I think Mitch
>pointed that out a few days back.
>
>If someone else has pointed this page out already forgive me, I haven't had
>any incoming mail for 24 hours or so and haven't seen the latest posts.
>
>Regards,
>
>Stewart Milton
>SRM Engineering cc
>srmilton@global.co.za or
>srm@technologist.com
>
------------------------------
Date: Fri, 14 Aug 1998 09:16:50 +1000
From: "Thacker, Heath HW"
Subject: RE: MC-Chassis Measuring lean angle etc.
In the article, they claim no-one has ever high-sided the bike.
Although, it sounds like it has spat off a few riders.
Heath.
> From: yhakim@m5.sprynet.com[SMTP:yhakim@m5.sprynet.com]
>
> Gary Rothwell rode the slide machine and manged to flip it!
>
> On Thu, 13 Aug 1998, "Stewart Roger Milton"
> wrote:
> >At the following site there's an interesting bike designed and used
> by
> >Keith Code for teaching leaning to extreme angles and sliding the
> rear
> >tyre. The device attached to the bike looks like it could easily be
> >modified for measuring lean angle, (and maybe stop you highsiding
> while you
> >do it!) although the attempt at measurement will change the system
> your
> >trying to evaluate!
> >
> >http://www.motorcycle.com/mo/mccustom/slide.html
> >
>
------------------------------
Date: Fri, 14 Aug 1998 09:33:46 +1000
From: "Thacker, Heath HW"
Subject: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
> From: batwings@i-plus.net[SMTP:batwings@i-plus.net]
>
> At 04:01 PM 8/13/98 +1000, you wrote:
> >On the rear say is currently about 1 inch. I was told if I reduced
> any
> >further, I'd be increasing the change of highsiding, as the
> suspension
> >would be topped out.
>
> It's your choice; you are bottoming out right now on the ground, no?
>
Well, the suspension isn't bottoming out, (as I've fitted stronger fork
springs & new rear shock for my weight), but yes, there are bits of my
bike scraping on the road.
> I
> doubt you'll highside it if you raise the seat hgt an inch. I
> seriously
> think whoever told you that hasn't got a clue.
>
Probably true, but his justification did make some sense. He said that
if the bike went to highside, the suspension (if not topped out), would
absorb some of the kick, and give you a greater chance of riding out of
it. I guess how much more chance is the question, probably very very
minor. ??
> of course the best answer might be stiffer springs.
>
The ride is already pretty stiff, I do want to be able to absorb some
bumps. :-)
> Let us know how you do next time you ride.
>
Thanks I will.
Regards,
Heath.
------------------------------
Date: Fri, 14 Aug 1998 09:41:23 +1000
From: "Thacker, Heath HW"
Subject: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
> From: Andy Overstreet[SMTP:bastich@swcp.com]
>
> Hi, Hoyt - I remember the magazines complaining about this particular
> model when it came out. Aren't there different suspension links
> available
> (Or can be made) to raise it? Would this be a good way to go if the
> spring
> is already stiff enough?
>
Thanks ! This sound like it could be the answer ! Anyone know of
anyone making these kits ? I think I remember seeing them before, but
was put off by someone telling me it would stuff up the steering
geometry. But if I only raise it as much as the front has been raised,
I should be back to normal. I guess there's no option for raising the
front further (if needed, to keep them in balance) except new longer
forks.
Thanks again,
Heath.
------------------------------
Date: Thu, 13 Aug 1998 18:21:59 -0800
From: "Michael Moore"
Subject: MC-Chassis (Fwd) RE: New Member Project
Les posted this on the mcmod list, and said it was OK to post here.
I thought you'd like it.
Cheers,
Michael
- ------- Forwarded Message Follows -------
From: Les Mulder
To: "'mcmod@research.canon.com.au'"
Subject: RE: New Member Project
Date: Wed, 12 Aug 1998 21:45:40 +1000
Reply-to: mcmod@research.canon.com.au
Megan Continued Writing:
>
>
>> things. Real innovation often comes from the small firm or
individuals
>> without formal training in the field. Think of Bimota, think of the
late
>> John Britten, think of Dr. Wittner."
>>
>> Young Ian may belong in that list too.
>
>Yeah. Except I have no experience at all at present and for beginning
>would rather not start something too ambitious (spelling?)
Gimme a break - from your comments over the last 24hrs, you didn't
exactly find this list & then say "Gee, what a good idea - I think I'd
like to modify a motorcycle." Sell yourself short at your own peril.
>
>
>>
>> >Anyone used/using plastics/fibres/composites for frames?
>> Yes & No. Building consistent, predictable structural composites with
>> adequate stiffness/strength/lightness seems beyond the capabilities
of
>> my home workshop (though maybe not yours).
>
>I am interested in hearing what you have tried. I havent' tried
anything
>yet.
>
OK - if you insist, here are some step-by-step instructions for
repeating my mistakes:
Disaster number one - Build something that looks like a cross between a
swingarm and a cardboard box out of balsa. Cover this with 6oz woven
fibreglass cloth & stick it all together with polyester resin. Make sure
there's plenty of resin, in order to wet the cloth out properly. Add
another layer of glass to further strengthen the structure & repeat the
resin torture. 3rd layer same as second. Now add a final layer of resin
in the hope that the finish will look less daggy.
Result? A composite structure that looks nothing like a swingarm, but
quite like a doll's cubby house made by a blind plumber.
Stiffness? About the same as al dente pasta.
Strength? About the same as the pasta before it was cooked.
Weight? 5% *more* than the original alloy item
Throw the resulting mess away.
Disaster number two - build swingarm to exact dimensions from balsa.
Seal with varnish, then wax with a release compound. build a female
mould around this (again out of glass & polyester) - bottom, inside &
outside surfaces only, to allow you to extract the balsa plug once the
mould is complete. When this has cured, lay up the missing piece, with
plenty of release compound, to make sure you can get it all apart &
extract the plug. Allow the whole thing to cure for a couple of days.
Spend one hour separating the two halves of the mould. Spend the rest of
the day trying to get the balsa plug out of the bottom half of the
mould.
Throw the resulting mess away.
Number 3 - try the mould thing again, but this time split it differently
- - build the inside & top together, with the outside & bottom as the
other half. Congratulate yourself on how easily the mould halves come
apart. Now take some foam core material (the expanded glass foam as used
by boaties is a good start) and carve blocks of it to fit the mould
exactly. Now wet lay up the outside half of the mould with woven rovings
as well as woven cloth, to maximise stiffness & strength. While this is
wet, lay your foam blocks in the mould so they bed down nicely in the
glass. Now lay up the other two sides directly onto the foam. When this
is done, put the other half of the mould in place & apply lots of
pressure to ensure the surfaces of the workpiece will be nice & smooth
(both pretty & lacking in stress raisers). Allow to cure in the mould
for around two days. Spend the following two days attempting to get the
mould apart without ruining either the mould or the workpiece. Ruin
both.
Throw the resulting mess away.
(I'm beginning to see a pattern by now)
Now is a good time to get those books I referred to in an earlier
e-mail. In words & pictures they do a much better job of describing the
processes of composite construction than this half-arsed plastics
artificer will ever manage...
Now that I've read up on the topic a bit more, I'm limiting myself to
wet lay up of some of the less critical structures such as fairings,
sidecovers and some less warm engine covers (clutch, etc). Maybe I'll
get brave & have a go at the seat/subframe as a unit. If I ever find a
way to access an autoclave I would like have a go at structural parts
again using carbon pre-pregs with honeycomb cores, as this is a
technique much better suited to the application.
Cheers,
Les
------------------------------
Date: Thu, 13 Aug 1998 19:57:34 -0800
From: "Michael Moore"
Subject: MC-Chassis Senor Bulto
Here's a clipping (in Spanish) from a Spanish news service announcing
Senor Bulto's death that was just posted on the vintage-dirt list:
ECONOMIA 05/08/98
- ----------------------------------------------------------------------
Muere el fundador de Bultaco y de Montesa
Francisco Bulto fallece a los 86 anos, pocos meses antes de ver
renacer su gran marca de motos de la mano de Derbi
RAYMOND BLANCAFORT
Barcelona
.............
>From everything I've heard he was a true gentleman and enthusiast,
and as a former Bultaco owner, I'm saddened by his passing.
Michael
------------------------------
End of MC-Chassis-Dgst V1 #724
******************************
MC-Chassis-Dgst Friday, August 14 1998 Volume 01 : Number 725
1. "Glenn Thomson" Subj: Re: MC-Chassis Romanelli FFE
2. Alan Lapp Subj: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
3. Eugene Shafir <04shafir@cua.edu> Subj: Re: MC-Chassis Tyre Loading & Lean angle Clearance.
4. batwings@i-plus.net Subj: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
5. Bill Heckel Subj: Re: MC-Chassis Tyre Loading & Lean angle. ( fork oil level )
6. "Michael Moore" Subj: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
7. Eugene Shafir <04shafir@cua.edu> Subj: Re: MC-Chassis Tyre Loading & Lean angle. ( fork oil level )
8. "Michael Moore" Subj: MC-Chassis Stiff frames
9. eric sherrer Subj: Re: MC-Chassis Stiff frames
10. "Michael Moore" Subj: MC-Chassis Aero - stability vs speed
----------------------------------------------------------------------
Date: Thu, 13 Aug 1998 22:06:40 +0000
From: "Glenn Thomson"
Subject: Re: MC-Chassis Romanelli FFE
On 11 Aug 98, Michael Moore wrote:
> The 10/98 issue of "Sport Rider" came today, and included an article
> on the Ducati with FFE designed by Franco Romanelli (they featured
> the 6 valve cylinder heads designed by FR in an earlier article, with
> just a teaser photo of the FFE).
>
> It looks to me the FFE is a Difazio/Tait/Bimota HCS with the lower
> arm moved up about 5 or 6 inches, a non-pivoting U-shaped upright
> that carries the stationary axle mounted to the two sets of arms, and
> the pivoting upright supported by the kingpin bearing and a bearing
> at the top of the stationary upright.
This wouldn't be his first, then. When he was in Montreal, he had
something with an FFE, which I seem to remember was a bit
like the twin head Phasar on Julian's Feet Forward site. This was
along with his car (HIS car) and a lot of other interesting stuff.
Cheers,
Glenn
gthomson(at)bserv.com
Waterloo, Ontario, CANADA
------------------------------
Date: Fri, 14 Aug 1998 00:05:03 +0100
From: Alan Lapp
Subject: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
>Thanks ! This sound like it could be the answer ! Anyone know of
>anyone making these kits ? I think I remember seeing them before, but
>was put off by someone telling me it would stuff up the steering
>geometry. But if I only raise it as much as the front has been raised,
>I should be back to normal. I guess there's no option for raising the
>front further (if needed, to keep them in balance) except new longer
>forks.
>
>Thanks again,
>Heath.
They were notorious for poor damping. My recommendation is to send the
forks to Race Tech or Traxxion Dynamics for revalving, polishing of the
orfices, and a Gold Valve cartridge emulator setup.
For the rear, I'd suggest a Fox shock: reasonably priced and fully
adjustable. This includes a ride height adjustment.
This is making the assumption that you've exhausted the possibilitites with
the stock setup. One fork setup parameter which is often overlooked is
fork oil height. By raising the fork oil level, the quantity of air (a
compressable gas as opposed to the non-compressable oil) is reduced. This
won't have any effect on initial travel, but will add a great deal of
progressivity in the top half of the compression stroke. This may have the
desired effect of increasing ground clearance since cornering force
compresses the suspension.
Al
level_5_ltd@earthlink.net
------------------------------
Date: Fri, 14 Aug 1998 14:17:33 -0400
From: Eugene Shafir <04shafir@cua.edu>
Subject: Re: MC-Chassis Tyre Loading & Lean angle Clearance.
Alan Lapp wrote:
>
> By raising the fork oil level, the quantity of air (a
> compressable gas as opposed to the non-compressable oil) is reduced.
Reducing the air pressure will give you the same result.
Eugene
------------------------------
Date: Thu, 13 Aug 1998 19:30:14
From: batwings@i-plus.net
Subject: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
At 06:01 AM 8/13/98 -0600, you wrote:
>Hi, Hoyt - I remember the magazines complaining about this particular
>model when it came out. Aren't there different suspension links available
>(Or can be made) to raise it? Would this be a good way to go if the spring
>is already stiff enough?
Well good grief I'm no GXSR expert and they may have had valid comments
about the ground clearance. <=Is that their complaint? All that said,
highsiding is a specific reaction I think to a peculiar set of
circumstances often following regaining traction after a slide, and I don't
see how ride height contributes to it.
Changing linkages will of course change all your suspension parameters, but
you should be able to get pretty close with springing only. If available
springs won't do it, altered or new links would be the next thing to go
with. As I recall the GXSEs used a dogbone suspended between bolt-on links
spanning to the frame, yes? Making a pair of them shouldn't be hard. I'll
bet Michael knows where you can buy them.
best wishes,
Hoyt
------------------------------
Date: Fri, 14 Aug 1998 17:39:54 -0400
From: Bill Heckel
Subject: Re: MC-Chassis Tyre Loading & Lean angle. ( fork oil level )
I think you mean RAISING the air pressure.
Actually, it won't give the same effect, decreasing the air space above the oil
gives a more rapid progressive action on the forks. You can take it to the
extreme, leave only 1" air space above the oil and when the wheel moves you get
very rapid rate progression as the air pressure skyrockets...
I don't think this is the recommended way of adding progression to forks but it
has been used on dirt bikes and old street bikes for a while as a 'quick fix',
just be sure not to overdo it or you will limit travel or blow seals.
Bill
Eugene Shafir wrote:
>
> Alan Lapp wrote:
> >
> > By raising the fork oil level, the quantity of air (a
> > compressable gas as opposed to the non-compressable oil) is reduced.
>
> Reducing the air pressure will give you the same result.
>
> Eugene
------------------------------
Date: Fri, 14 Aug 1998 16:11:19 -0800
From: "Michael Moore"
Subject: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
> >model when it came out. Aren't there different suspension links available
> with. As I recall the GXSEs used a dogbone suspended between bolt-on links
> spanning to the frame, yes? Making a pair of them shouldn't be hard. I'll
> bet Michael knows where you can buy them.
Hello Hoyt,
Not this time I don't. I remember an article on them, probably in
RW&MT, but that was some years ago, and since I never raced/owned
anything like that I didn't keep in mind any of the details, other
than it was supposed to be a noticeable improvement over stock.
Cheers,
Michael
------------------------------
Date: Fri, 14 Aug 1998 19:24:35 -0400
From: Eugene Shafir <04shafir@cua.edu>
Subject: Re: MC-Chassis Tyre Loading & Lean angle. ( fork oil level )
Bill Heckel wrote:
>
> I think you mean RAISING the air pressure.
Exactly, that's what I meant.
Eugene
------------------------------
Date: Fri, 14 Aug 1998 17:18:12 -0800
From: "Michael Moore"
Subject: MC-Chassis Stiff frames
The new issue of RW&MT has a roadtest on the Aprilia RSV1000. In it,
John Ulrich mentions discussing with the chassis designer (Gaetano
Cocco, formerly of the Aprilia race department) "the question of
whether it is possibile to make a frame too rigid (so far, every time
the Aprilia engineers have made a racing frame more rigid, it has
worked better, he told me)."
Cheers,
Michael
------------------------------
Date: Fri, 14 Aug 1998 18:08:47 -0700
From: eric sherrer
Subject: Re: MC-Chassis Stiff frames
Michael wrote;
>"The new issue of RW&MT has a roadtest on the Aprilia RSV1000. In it,
>John Ulrich mentions discussing with the chassis designer (Gaetano
>Cocco, formerly of the Aprilia race department) "the question of
>whether it is possibile to make a frame too rigid (so far, every time
>the Aprilia engineers have made a racing frame more rigid, it has
>worked better, he told me)."
I was also interested in the torsional ridgity number they quoted for
the frame, i.e. "4701 lbs-ft/degree". In the same issue, an article on
the Donington GP had some quotes from Team Suzuki on the same subject;
"Team Suzuki has been experimenting with controlled flex chassis...
..This type of chassis is a step beyond the old ideal of making the
structure as stiff as possible. The old pattern led to sophisticated
problems at high lean angles, when the suspension can no longer absorb
bumps in the normal way. The new design introduces controlled compliance
to compensate for this problem..."
FWIW, Eric
------------------------------
Date: Fri, 14 Aug 1998 20:19:47 -0800
From: "Michael Moore"
Subject: MC-Chassis Aero - stability vs speed
Another snippet from the new RW&MT:
Davy Widjaja, a racer and aerodynamicist (I think he was the one who
did the "Rhino" front fender) says that while you can gain about 5
mph on a 120 bhp bike by working on the aerodynamics, handling and
stability, especially in crosswinds, will deteriorate very noticably.
He says that design compromises that will be needed will limit top
speed increase to 3 mph. He also says that is why the Modenas riders
reported handling problems with the Lotus-designed seat/fairing.
Cheers,
Michael
------------------------------
End of MC-Chassis-Dgst V1 #725
******************************
MC-Chassis-Dgst Sunday, August 16 1998 Volume 01 : Number 726
1. batwings@i-plus.net Subj: Re: MC-Chassis Stiff frames
2. "Michael Moore" Subj: MC-Chassis FFE Ducati
3. camillieri@earthlink.net Subj: Re: MC-Chassis Stiff frames
4. "D Hixon" Subj: Re: MC-Chassis Tyre Loading & Lean angle Clearance.
----------------------------------------------------------------------
Date: Sat, 15 Aug 1998 06:49:05
From: batwings@i-plus.net
Subject: Re: MC-Chassis Stiff frames
At 06:08 PM 8/14/98 -0700, you wrote:
>Michael wrote;
>
>>"The new issue of RW&MT has a roadtest on the Aprilia RSV1000. In it,
>>John Ulrich mentions discussing with the chassis designer (Gaetano
>>Cocco, formerly of the Aprilia race department) "the question of
>>whether it is possibile to make a frame too rigid (so far, every time
>>the Aprilia engineers have made a racing frame more rigid, it has
>>worked better, he told me)."
>
>I was also interested in the torsional ridgity number they quoted for
>the frame, i.e. "4701 lbs-ft/degree". In the same issue, an article on
>the Donington GP had some quotes from Team Suzuki on the same subject;
>
> "Team Suzuki has been experimenting with controlled flex chassis...
>..This type of chassis is a step beyond the old ideal of making the
>structure as stiff as possible. The old pattern led to sophisticated
>problems at high lean angles, when the suspension can no longer absorb
>bumps in the normal way. The new design introduces controlled compliance
>to compensate for this problem..."
Let's see what this really means... Suzi sez faster bikes have increasingly
more sophisticated problems when leaning over and they are experimenting
with controlled flex. I thought that was what suspension was for, but the
critical point is that they don't say it's better, nor do they or anyone
else ever characterize exactly what must flex and how much, to relieve the
burden of the problems.
Aprilia, OTOH, sez quite clearly that stiffer frames always work better and
as far as I can tell, they prove it at every race they enter. That is my
own experience also in both dirt and on the asphalt.
To my mind this is quite conclusive and quite in keeping with present
theory, and if the flexie-flyer folks wish to counter-prove it, they have
some serious parameter-defining to do. So far no-one who ever advocated
flex in a frame including Tony has ever been able to do that. That's a big
QED, babay, in my headbone. Anyone wishing to prove otherwise has only to
loosen some stuff up -- like SA bolt or fork clamps, to produce some flex
- -- and see for hisself.
Hoyt
------------------------------
Date: Sat, 15 Aug 1998 14:18:22 -0800
From: "Michael Moore"
Subject: MC-Chassis FFE Ducati
The 05 August edition of the UK newspaper "Motor Cycle News" arrived
today, and there is a 2 page article on the new 996 Ducati. It wil
have a Foale/Parker-style front end, with the lower single-sided
swing arm attaching to the upright above the front axle, about 1/2
way along the upright. An articulated scissors linkage is shown to
connect the upright to the handlebars (a la ASP).
Other than that, the only big difference seems to be that "it will
have a carbon-fibre chainguard to shave weight".
Cheers,
Michael
------------------------------
Date: Sat, 15 Aug 1998 19:37:10 -0400
From: camillieri@earthlink.net
Subject: Re: MC-Chassis Stiff frames
>
> Let's see what this really means... Suzi sez faster bikes have increasingly
> more sophisticated problems when leaning over and they are experimenting
> with controlled flex. I thought that was what suspension was for, but the
> critical point is that they don't say it's better, nor do they or anyone
> else ever characterize exactly what must flex and how much, to relieve the
> burden of the problems.
>
> Aprilia, OTOH, sez quite clearly that stiffer frames always work better and
> as far as I can tell, they prove it at every race they enter. That is my
> own experience also in both dirt and on the asphalt.
>
> To my mind this is quite conclusive and quite in keeping with present
> theory, and if the flexie-flyer folks wish to counter-prove it, they have
> some serious parameter-defining to do. So far no-one who ever advocated
> flex in a frame including Tony has ever been able to do that. That's a big
> QED, babay, in my headbone. Anyone wishing to prove otherwise has only to
> loosen some stuff up -- like SA bolt or fork clamps, to produce some flex
> -- and see for hisself.
>
>
> Hoyt
When I was building frames for Kevin Cameron's H2 Kaw we sort of
decided that if the frame was stiff enough the head angle and trail
wasn't too important. I think we got down to about 26 degrees and
never had to use a steering damper.
Frank Camillieri
Chester, NH
------------------------------
Date: Sun, 16 Aug 1998 15:52:02 -0400
From: "D Hixon"
Subject: Re: MC-Chassis Tyre Loading & Lean angle Clearance.
About the GSX-R links: Dale Rathwell made them for the '88-'89's; I *think*
Fox took that over, but I'm not sure on it. Supposedly they were the hot
ticket.
Another '88-'89 tidbit: the Computrack guys told me that those frames
were very close to perfect geometry out of the box.
Have fun,
Ray Hixon
(sometimes wish I hadn't sold my '89)
------------------------------
End of MC-Chassis-Dgst V1 #726
******************************
MC-Chassis-Dgst Monday, August 17 1998 Volume 01 : Number 727
1. batwings@i-plus.net Subj: Re: MC-Chassis Stiff frames
2. "Tony Foale" Subj: MC-Chassis Re: Flex again.
3. "Tony Foale" Subj: Re: MC-Chassis-Dgst V1 #726
4. Fredric Martinson <2feetup@coffey.com> Subj: MC-Chassis Chassis jig
5. Bill Heckel Subj: Re: MC-Chassis Chassis jig
6. "john.mead" Subj: Re: MC-Chassis Chassis jig
7. "Frank Camillieri" Subj: Re: MC-Chassis Stiff frames
8. Mitch Casto Subj: MC-Chassis Naive question- Motorcycle RAKE / Automotive CASTER Synonymous?
9. "Frank Camillieri" Subj: MC-Chassis Stiff frames
10. "Frank Camillieri" Subj: MC-Chassis Rake
11. "Michael Moore" Subj: Re: MC-Chassis Stiff frames
12. "Frank Camillieri" Subj: Re: MC-Chassis Stiff frames
13. batwings@i-plus.net Subj: Re: MC-Chassis Re: Flex again.
----------------------------------------------------------------------
Date: Sun, 16 Aug 1998 08:11:41
From: batwings@i-plus.net
Subject: Re: MC-Chassis Stiff frames
At 07:37 PM 8/15/98 -0400, you wrote:
>When I was building frames for Kevin Cameron's H2 Kaw we sort of
>decided that if the frame was stiff enough the head angle and trail
>wasn't too important. I think we got down to about 26 degrees and
>never had to use a steering damper.
I am expert witness in vehicle dynamics and handling issues. Had a case
once where the bike went ape-shit and left 177' of front wheel skid marks
on the road before crashing in a ditch, sort of the best example of a
wobble you will ever hear about. In working on this case with a most
generous employer, I spent a lot of time on the phone, including some
interesting conversations with Erik Buell. His opinion was almost exactly
the same: if the chassis is appropriately designed and kept things lined
up, your fork rake, trail, SA length, etc, hardly mattered.
I have about decided that rake IS important, but for a reason never
mentioned: when the fork is more vertical, the slop in the fork bushings is
more evident and so are steering effects of it. If the fork is raked out
some, the play in the bushings is taken care of by the bending load on the
legs, hence the fork is preloaded against the play and it acts more rigid.
That is most likely the reason for a generally-observed proscription
against steep forks, coming to all of us as a hand-me-down but not
understood rule of construction.
Best wishes,
Hoyt
------------------------------
Date: Mon, 17 Aug 1998 00:25:19 +0200
From: "Tony Foale"
Subject: MC-Chassis Re: Flex again.
Ollie said,
<<
So far no-one who ever advocated
flex in a frame including Tony has ever been able to do that.
>>
Ollie, why is it that whenever this topic arises you seem determined to put
words in my mouth? This is not the first time on this list that you've
tried to intimate that I've advocated flex.
I defy you to find any such reference.
However, I'm neither idiotic nor closeminded enough not to be able to
understand the problems that those advocating lateral flex are trying to
cure. Despite your refusals to accept this, the problems have been well
enough explained on this list before.
My stance is and always has been, that I can see the problem but I don't
think that introducing lateral flex into the frame as currently being talked
about is the correct solution to these problems, ultimately I would agree
that the cure will be worse than the disease.
I don't claim to have a solution other than suggesting that the place to
start looking is in tyre technology and active suspension.
I'm certainly not simple minded enough to think your suggestion of just
increasing suspension movement in a plane at right angles to the troublesome
forces is an appropriate cure either.
<<
Anyone wishing to prove otherwise has only to
loosen some stuff up -- like SA bolt or fork clamps, to produce some flex
>>
I think you must have a very low opinion of this list's collective
intelligence, if you expect anybody on it to seriously expect similar
reponses from your suggestions and the behaviour of a bike deliberately
setup to absorb lateral loads. If indeed the quoted Suzuki handled
similarly to loosening some bolts, as you suggest, then are we to seriously
imagine that it would have been ridden more than once anywhere other than at
a test track?
- ---------------
There really is no need to try to put words into my mouth, you know, I'm
quite capable of doing that for myself.
Tony Foale
España ( Spain )
http://www.ctv.es/USERS/softtech/motos
------------------------------
Date: Mon, 17 Aug 1998 00:27:52 +0200
From: "Tony Foale"
Subject: Re: MC-Chassis-Dgst V1 #726
Frank said,
<<
. I think we got down to about 26 degrees and
never had to use a steering damper.
>>
I got down to 0 degrees and never had to use a steering damper.
Next bid, please!
Tony Foale
España ( Spain )
http://www.ctv.es/USERS/softtech/motos
------------------------------
Date: Sun, 16 Aug 1998 17:23:47 -0600
From: Fredric Martinson <2feetup@coffey.com>
Subject: MC-Chassis Chassis jig
Hi all,
I found a book on motorcycle chassis (Harley's) custom building of frames,
at a Barnes and Nobles store. The best part is chapter 9 where they show
two differant frame jig's used by custom frame builders.
Ultimate V-Twin Motorcycle Chassis
by Timothy Remus
ISBN number: 0-9641358-7-6
published by
Wolfgang Publications Inc
PO Box 10
Scandia, MN
55073
Fred
------------------------------
Date: Sun, 16 Aug 1998 20:19:50 -0400
From: Bill Heckel
Subject: Re: MC-Chassis Chassis jig
Wow, I saw that book also, I am always amazed what one can accomplish with a
saw horse, a couple of 2x4 and some bungee cords. ;}
Fredric Martinson wrote:
> I found a book on motorcycle chassis (Harley's) custom building of frames,
> at a Barnes and Nobles store. The best part is chapter 9 where they show
> two differant frame jig's used by custom frame builders.
>
Bill
P.S. I am kidding :)
------------------------------
Date: Sun, 16 Aug 1998 10:14:19 -0700 (PDT)
From: "john.mead"
Subject: Re: MC-Chassis Chassis jig
In the transportation section of my local Barnes and Nobles, I saw similar
books on John Deere and Ferguson custom frames.
John Mead
- ----------
> Hi all,
>
> I found a book on motorcycle chassis (Harley's) custom building of frames,
> at a Barnes and Nobles store. The best part is chapter 9 where they show
> two differant frame jig's used by custom frame builders.
>
> Ultimate V-Twin Motorcycle Chassis
> by Timothy Remus
> ISBN number: 0-9641358-7-6
> published by
> Wolfgang Publications Inc
> PO Box 10
> Scandia, MN
> 55073
>
> Fred
>
------------------------------
Date: Sun, 16 Aug 1998 23:35:15 -0400
From: "Frank Camillieri"
Subject: Re: MC-Chassis Stiff frames
Hoyt,
I'm racing a 500 Triumph with a frame I built in 68. It handles very well and when
I take it apart I will measure it and let you know how straight it is. I did manage
to crash it once this weekend but it never hit anything! I have measured the SA
and found it to be about .060 out from pivot to axle.
Regards,
Frank
Frank Camillieri
Chester, NH
------------------------------
Date: Sun, 16 Aug 1998 23:37:49 -0400
From: Mitch Casto
Subject: MC-Chassis Naive question- Motorcycle RAKE / Automotive CASTER Synonymous?
Rake debaters:
I have a naive question: is motorcycle front suspension rake
synonymous with automotive caster?
A defining illustration of automotive caster can be found at:
http://www.automotion.com/Cat9.html
A brief bit about the importance of caster settings of race cars can be
seen at:
http://www.ground-control.com
and an e-mail list discussion by go-cart racers about Caster is at:
http://www.cynical.net/hypermail/karting.jan15-feb20/1364.html
It interests me that the 'ground control' site talks of a caster range
of only 3.5 to 5 degrees. When I think of any kind of 4 wheeled vehicle,
a caster/rake of 26 or more degrees seems weird. I can't picture any
sorts of conditions that this would be useful on any kind of 4 wheeled
vehicle application from pool table smooth race tracks to extreme
off-road racing.
Is there some difference between 4-wheeled vehicles and motorcycles that
I'm missing in this analysis?
Are caster and rake synonymous?
mitch
Tony Foale wrote:
> Frank said,
>
> <<
> . I think we got down to about 26 degrees and
> never had to use a steering damper.
> >>
>
> I got down to 0 degrees and never had to use a steering damper.
> Next bid, please!
>
> Tony Foale
>
> España ( Spain )
> http://www.ctv.es/USERS/softtech/motos
------------------------------
Date: Sun, 16 Aug 1998 23:48:40 -0400
From: "Frank Camillieri"
Subject: MC-Chassis Stiff frames
Why are so many racers obsessed with unsprung weight to the point of putting
soft, small diameter aluminium spacers on their axles. I just bored out a
backing plate that had wear marks in it from the SA and installed steel
bushings with large heads to bear on the SA plates. I would think a stiff SA is
much more important than a little extra unsprung weight.
Regards,
Frank
Frank Camillieri
Chester, NH
------------------------------
Date: Sun, 16 Aug 1998 23:53:13 -0400
From: "Frank Camillieri"
Subject: MC-Chassis Rake
Tony,
Did anyone ever try to race with 0 degrees?
Regards,
Frank
Frank Camillieri
Chester, NH
------------------------------
Date: Sun, 16 Aug 1998 21:15:39 -0800
From: "Michael Moore"
Subject: Re: MC-Chassis Stiff frames
> Why are so many racers obsessed with unsprung weight to the point of putting
> soft, small diameter aluminium spacers on their axles. I just bored out a
> backing plate that had wear marks in it from the SA and installed steel
> bushings with large heads to bear on the SA plates. I would think a stiff SA is
> much more important than a little extra unsprung weight.
Hello Frank,
It is much easier and more enjoyable to get a better sprung to
unsprung weight ratio by upping the rider's the intake of milkshakes
and burgers.
A lot of people don't seem to be aware that there are different
grades/hardness of aluminum and steel. Joe/Jane Racer is probably
just as likely to go out and say "1100-H0, pure aluminum that must be
just what I need for my wheel spacers" as to get 6061 or 7075-T6,
which might actually do the job.
Steel is wonderful stuff, but I was aghast when I looked at the stock
ferrous wheel spacers on the back of a SuperHawk that were easily
bigger than a non-squidgy aluminum spacer could have been.
Cheers,
Michael
------------------------------
Date: Mon, 17 Aug 1998 07:20:04 -0400
From: "Frank Camillieri"
Subject: Re: MC-Chassis Stiff frames
Hi Michael,
Honda tended to go overboard on those Hawks. It must have the heaviest
engine to displacement weight ratio ever produced. Years ago someone told
me they used zinc in their castings because the junk aluminum was porous.
Regards,
Frank
Frank Camillieri
Chester, NH
------------------------------
Date: Mon, 17 Aug 1998 09:30:25
From: batwings@i-plus.net
Subject: Re: MC-Chassis Re: Flex again.
At 12:25 AM 8/17/98 +0200, you wrote:
>Ollie, why is it that whenever this topic arises you seem determined to put
>words in my mouth? This is not the first time on this list that you've
>tried to intimate that I've advocated flex.
>I defy you to find any such reference.
I can't find it coz I don't keep old mail for such opportunities, but you
definitely once said something to the effect that a very good rider could
go faster on a bike which had a bit of flex to relieve the effects of
suspensions not working well when they are loaded from the edge of the
tire, or sideways. This was in response to my assertion that all one needed
to make 125s faster was more travel (and frames commensurate with the task
of controlling it). My question then and now was that if a lesser-talented
rider could go faster with a good stiff frame vs a flexie-flyer frame, but
a very good rider could use the flex, then what a rational theory exists as
to why?
> Despite your refusals to accept this, the problems have been well
>enough explained on this list before.
Don't put words in my mouth, please. I'm quite aware of the problems and
agree with Aprilia as to how to fix them.
>I think you must have a very low opinion of this list's collective
>intelligence, if you expect anybody on it to seriously expect similar
>reponses from your suggestions and the behaviour of a bike deliberately
>setup to absorb lateral loads.
If I had stated the comment was limited to the list members, you might be
more correct, but I didn't intend for anyone to think I meant they were all
that stupid and I hardly need to explain that this was largely a rhetorical
comment.
There is, however a grand correspondance between flex at the SA pivot area
however provided for and a loose SA bolt, and you are correct to agree that
the cure would be worse than the disease, as lateral rigidity was almost
the entire theme of the theoreticians and computer modelers at the SAE
Symposium on MC dynamics in 1978.
Best wishes,
Hoyt
------------------------------
End of MC-Chassis-Dgst V1 #727
******************************
MC-Chassis-Dgst Monday, August 17 1998 Volume 01 : Number 728
1. batwings@i-plus.net Subj: Re: MC-Chassis Stiff frames
2. batwings@i-plus.net Subj: Re: MC-Chassis Stiff frames
3. batwings@i-plus.net Subj: Re: MC-Chassis Stiff frames
4. Alan Lapp Subj: Re: MC-Chassis Naive question- Motorcycle RAKE / Automotive CASTER Synonymous?
5. yhakim@m5.sprynet.com Subj: MC-Chassis tuned flex chassis
6. yhakim@m5.sprynet.com Subj: MC-Chassis tuned flex chassis
7. "Thomas Alberti" Subj: Re: MC-Chassis Naive question- Motorcycle RAKE / Automotive CASTER Synonymous?
8. "Tony Foale" Subj: MC-Chassis Re: Castor angle
9. Marty Maclean Subj: Re: MC-Chassis tuned flex chassis
10. Marty Maclean Subj: Re: MC-Chassis tuned flex chassis
11. "Tony Foale" Subj: MC-Chassis Re: Misquotes
12. "Frank Camillieri" Subj: Re: MC-Chassis Stiff frames
13. "Calvin Grandy" Subj: Re: MC-Chassis Stiff frames
14. batwings@i-plus.net Subj: Re: MC-Chassis Stiff frames
15. "Jim Schneider" Subj: Re: MC-Chassis Stiff frames
----------------------------------------------------------------------
Date: Mon, 17 Aug 1998 07:53:40
From: batwings@i-plus.net
Subject: Re: MC-Chassis Stiff frames
At 11:48 PM 8/16/98 -0400, you wrote:
>Why are so many racers obsessed with unsprung weight to the point of putting
>soft, small diameter aluminium spacers on their axles?
>much more important than a little extra unsprung weight.
Listen to this guy... I have spent a lot of time replacing Al spacers with
steel. Have seen only one bit of Al in my life which I thought up to the
job: the SA nose spacer in a TZ250. It was Al but of some super alloy, and
it was anodized and so hard I could barely get the burrs off the ends where
it had been battered a bit by a previous mechanic.
Hoyt
------------------------------
Date: Mon, 17 Aug 1998 09:31:05
From: batwings@i-plus.net
Subject: Re: MC-Chassis Stiff frames
At 09:15 PM 8/16/98 -0800, you wrote:
>It is much easier and more enjoyable to get a better sprung to
>unsprung weight ratio by upping the rider's the intake of milkshakes
>and burgers.
is that why I'm getting slower?
>
>Steel is wonderful stuff, but I was aghast when I looked at the stock
>ferrous wheel spacers on the back of a SuperHawk that were easily
>bigger than a non-squidgy aluminum spacer could have been.
I have some of those SH spacers in the basement right now and they don't
look bad to me. The best design will have the cross-sectional area of
spacer equal to that of the axle, producing equal stresses in service. But
there is a problem with the mating surfaces in any case, and alignment and
grip both improve with spacers having end-flanges much larger than that,
and they are less likely to dig in and damage paint, plating and Al SAs.
best wishes,
Hoyt
------------------------------
Date: Mon, 17 Aug 1998 09:31:20
From: batwings@i-plus.net
Subject: Re: MC-Chassis Stiff frames
At 07:20 AM 8/17/98 -0400, you wrote:>
>Honda tended to go overboard on those Hawks. It must have the heaviest
>engine to displacement weight ratio ever produced. Years ago someone told
>me they used zinc in their castings because the junk aluminum was porous.
That motor weighed over 110 lbs, or over 7 lbs/cu in. Many aircraft motors
weigh no more than ~2 lbs/cu in. But the castings if they had zinc in them
had little, as they looked and machined exactly like all other aluminum
castings in my experience. I think yer pal must have been de-rating the
Japanese, who in reality have never been techno-challenged.
Hoyt
------------------------------
Date: Mon, 17 Aug 1998 10:28:02 +0100
From: Alan Lapp
Subject: Re: MC-Chassis Naive question- Motorcycle RAKE / Automotive CASTER Synonymous?
>Is there some difference between 4-wheeled vehicles and motorcycles that
>I'm missing in this analysis?
>
>Are caster and rake synonymous?
Superficially, yes they are. Both build trail into the system. Trail
provides self-centering force.
However, a 4 wheel vehicle operates radically diferently in 2 aspects:
First, the tires of a 4-wheeler have a flat and wide contact patch, and do
not roll.
Second, the 4-wheeler suspension system is very diferent, with the axis of
the kingpin well inboard of the center of the contact patch. The
suspension also moves along a diferent arc than the caster angle, contrary
to telescopic forks. If a telescopic fork were mounted at 3~4 degree rake,
flex and binding would likely be serious problem. 4-wheeler suspensions
have trailing links to isolate fore and aft forces from the suspension
units.
I'm not up to speed with the physics, I'm just making observations.
Al
level_5_ltd@earthlink.net
------------------------------
Date: Mon, 17 Aug 1998 08:30:47 -0700
From: yhakim@m5.sprynet.com
Subject: MC-Chassis tuned flex chassis
Much has been said both for and against tuned flex chassis, both on
this list and in printed media. I think everyone can agree that when in
full Fogarty cornering mode, it would be nice to have suspension
working in the direction of the bumps. Whether tuned flex is eventually
cast aside like oval pistons, Honda should still be admired for trying
something new.
Like anything else tuned flex is a comprimise
------------------------------
Date: Mon, 17 Aug 1998 08:35:55 -0700
From: yhakim@m5.sprynet.com
Subject: MC-Chassis tuned flex chassis
Sorry, my silly email program sent my mail too soon.
Tuned flex chassis probably work at tracks where you spend a lot of
time leaned way over. I believe a NSR250, with tuned flex, beat a lap
record set by Harada (on the TZM250 at the time).
Now having said all that I don't understand why I've never seen Honda
try anything with the 125's. They rely on high speed, extreme lean
angles more than most classes.
------------------------------
Date: Mon, 17 Aug 1998 12:32:24 -0500
From: "Thomas Alberti"
Subject: Re: MC-Chassis Naive question- Motorcycle RAKE / Automotive CASTER Synonymous?
> Is there some difference between 4-wheeled vehicles and motorcycles that
> I'm missing in this analysis?
A motorcycle tire has a round profile, a car tire has a rectangular
profile.
Thomas
------------------------------
Date: Mon, 17 Aug 1998 19:33:20 +0200
From: "Tony Foale"
Subject: MC-Chassis Re: Castor angle
Frank asked:
>>Did anyone ever try to race with 0 degrees?
I don't know of any. Various people have raced with various FFEs. and so I
expect that around 15deg. has been used.
Tony Foale
España ( Spain )
http://www.ctv.es/USERS/softtech/motos
------------------------------
Date: Mon, 17 Aug 1998 10:36:22 -0700
From: Marty Maclean
Subject: Re: MC-Chassis tuned flex chassis
yhakim@m5.sprynet.com wrote:
>
> Much has been said both for and against tuned flex chassis, both on
> this list and in printed media. I think everyone can agree that when in
> full Fogarty cornering mode, it would be nice to have suspension
> working in the direction of the bumps.
I don't know... I think I'd suggest that more folks would rather have a
chassis that kept everything is the correct, desired relationship to
each other - including Carl.
Marty
------------------------------
Date: Mon, 17 Aug 1998 10:37:28 -0700
From: Marty Maclean
Subject: Re: MC-Chassis tuned flex chassis
yhakim@m5.sprynet.com wrote:
>
> Sorry, my silly email program sent my mail too soon.
> Tuned flex chassis probably work at tracks where you spend a lot of
> time leaned way over. I believe a NSR250, with tuned flex, beat a lap
> record set by Harada (on the TZM250 at the time).
> Now having said all that I don't understand why I've never seen Honda
> try anything with the 125's. They rely on high speed, extreme lean
> angles more than most classes.
Maybe they should be replacing their spokes with bungee cords...
Marty
------------------------------
Date: Mon, 17 Aug 1998 19:56:56 +0200
From: "Tony Foale"
Subject: MC-Chassis Re: Misquotes
Ollie said:
>>I can't find it coz I don't keep old mail for such opportunities
You can't find it simply because I never said it, I have always advocted
stiffness and made that quite plain when this subject was broached before,
yet then as now, for motives best known to yourself, you seemed to want to
give the opposite impression.
<<
lateral rigidity was almost
the entire theme of the theoreticians and computer modelers at the SAE
Symposium on MC dynamics in 1978.
>>
Some themes were as you state, that's quite true, but none of the work was
aimed at, nor considered, the specific problem that Suzuki amongst others
are trying to cure.
Tony Foale
España ( Spain )
http://www.ctv.es/USERS/softtech/motos
------------------------------
Date: Mon, 17 Aug 1998 14:15:26 -0400
From: "Frank Camillieri"
Subject: Re: MC-Chassis Stiff frames
Hoyt,
That TZ spacer was probably hard coat anodized. It's only about .002 thick but
super hard. It's something like what they use in grinding wheels. I never thought
about having spacers hard coated and we have a lot of parts hard anodized at
our shop. I think it's worth trying.
Regards,
Frank
Frank Camillieri
Chester, NH
------------------------------
Date: Mon, 17 Aug 1998 14:42:16 -0400
From: "Calvin Grandy"
Subject: Re: MC-Chassis Stiff frames
Anodized aluminum is several times harder than the parent material,
aluminum. Al2O3 being the gemstone, garnet. Anodized surface
coating makes subsequent welding troublesome because of the increased
melting temperatures associated with the oxide form. Hard coat
Anodizing differs from the cosmetic color coating mostly by the depth
of conversion. The color is achieved by dyes.
In my work (Optical coatings) many refractory oxides of exotic metals
are used, Zirconia Titania, Tantala. Hafnia. Scandia,Alumina,and
Silica to name a few. These materials are sometimes converted from
the parent pure metal in our process.
Regards
Calvin Grandy
- ----------
> From: Frank Camillieri
> To: mc-chassis-design@list.sirius.com
> Subject: Re: MC-Chassis Stiff frames
> Date: Monday, August 17, 1998 2:15 PM
>
> Hoyt,
>
> That TZ spacer was probably hard coat anodized. It's only about
.002 thick but
> super hard. It's something like what they use in grinding wheels. I
never thought
> about having spacers hard coated and we have a lot of parts hard
anodized at
> our shop. I think it's worth trying.
>
> Regards,
> Frank
>
>
>
>
> Frank Camillieri
> Chester, NH
------------------------------
Date: Mon, 17 Aug 1998 14:54:12
From: batwings@i-plus.net
Subject: Re: MC-Chassis Stiff frames
At 02:15 PM 8/17/98 -0400, you wrote:
>Hoyt,
>
>That TZ spacer was probably hard coat anodized. It's only about .002 thick
but
>super hard. It's something like what they use in grinding wheels.
it's exactly the same stuff: aluminum oxide. it is a very hard material
with good adhesion to the base, and the stiffness goes up beyond belief.
>about having spacers hard coated and we have a lot of parts hard anodized
at >our shop. I think it's worth trying.
Let us know how it affects things,wilya?
Hoyt
>
------------------------------
Date: Mon, 17 Aug 1998 13:09:00 -0600
From: "Jim Schneider"
Subject: Re: MC-Chassis Stiff frames
Of course, it always helps to use some 7075-T6 for the material. That will
make a BIG difference in strength. All these years I have been throwing
those steel spacers away and I could have been selling them to Hoyt!!
Jim
Swiss
- -----Original Message-----
Subject: Re: MC-Chassis Stiff frames
Hoyt,
That TZ spacer was probably hard coat anodized. It's only about .002 thick
but
super hard. It's something like what they use in grinding wheels. I never
thought
about having spacers hard coated and we have a lot of parts hard anodized at
our shop. I think it's worth trying.
Regards,
Frank
------------------------------
End of MC-Chassis-Dgst V1 #728
******************************
MC-Chassis-Dgst Monday, August 17 1998 Volume 01 : Number 729
1. "Griffiths, Duncan" Subj: Re: MC-Chassis Stiff frames
2. "Griffiths, Duncan" Subj: Re: MC-Chassis Stiff frames
3. "Griffiths, Duncan" Subj: RE: MC-Chassis tuned flex chassis
4. Marty Maclean Subj: Re: MC-Chassis tuned flex chassis
5. GD Subj: MC-Chassis Inertia Dyno Math Needed !
6. yhakim@m5.sprynet.com Subj: RE: MC-Chassis tuned flex chassis
7. camillieri@earthlink.net Subj: MC-Chassis Stiff frames
8. "Jim Schneider" Subj: Re: MC-Chassis Stiff frames
9. "Jim Schneider" Subj: Re: MC-Chassis Stiff frames
10. "Michael Moore" Subj: Re: MC-Chassis Stiff frames
11. Dick Brewster Subj: MC-Chassis Hard Anodize
12. "Jim Schneider" Subj: Re: MC-Chassis Stiff frames
----------------------------------------------------------------------
Date: Mon, 17 Aug 1998 12:37 -0800
From: "Griffiths, Duncan"
Subject: Re: MC-Chassis Stiff frames
There's nothing wrong with less unsprung weight. I goes to show that
anything can be done poorly. The appropriate grade of aluminium (7075?)
or a hard-anodized piece (I don't think 7075 anodizes well) would do the
job more than adequately.
The anodizing has to be _hard_, not just the colored treatments.
Duncan
=============
>Why are so many racers obsessed with unsprung weight to the point of
putting
>soft, small diameter aluminium spacers on their axles?
>much more important than a little extra unsprung weight.
------------------------------
Date: Mon, 17 Aug 1998 12:42 -0800
From: "Griffiths, Duncan"
Subject: Re: MC-Chassis Stiff frames
That might have been mine you were working on. The axle spacers seem to
be of the same material/hardness and they do have large flanges at both
ends. The TZ at least does little things like this properly.
Duncan
======================
Have seen only one bit of Al in my life which I thought up to the
job: the SA nose spacer in a TZ250. It was Al but of some super alloy,
and
it was anodized and so hard I could barely get the burrs off the ends
where
it had been battered a bit by a previous mechanic.
The best design will have the cross-sectional area of
spacer equal to that of the axle, producing equal stresses in service.
But
there is a problem with the mating surfaces in any case, and alignment
and
grip both improve with spacers having end-flanges much larger than that,
and they are less likely to dig in and damage paint, plating and Al SAs.
Hoyt
------------------------------
Date: Mon, 17 Aug 1998 12:51 -0800
From: "Griffiths, Duncan"
Subject: RE: MC-Chassis tuned flex chassis
I don't think the tuned flex works anywhere. The longer you would be
leaned over, the more undamped oscillations it can get itself into. I've
found significant improvements in moving from the '91 TZ to a '93, which
has a significantly stiffer chassis.
The broken lap record may have been obliterated by a rigid bike that had
an equivalent engine spec to the NSR. A TZM is not in the same league as
an NSR.
The 125's rely on corner speed high lean angle. The last thing they
would want is to have the chassis do something uncontrolled at the limit.
Honda's grand experiment might work well for making street bikes more
comfortable on rough pavement when not riding at the limit, but it does
not make sense for true racing machines. Enough riders have tried and
abandoned it to make that fairly clear.
Duncan
====================
From: yhakim@m5.sprynet.com
Tuned flex chassis probably work at tracks where you spend a lot of
time leaned way over. I believe a NSR250, with tuned flex, beat a lap
record set by Harada (on the TZM250 at the time).
Now having said all that I don't understand why I've never seen Honda
try anything with the 125's. They rely on high speed, extreme lean
angles more than most classes.
------------------------------
Date: Mon, 17 Aug 1998 14:08:01 -0700
From: Marty Maclean
Subject: Re: MC-Chassis tuned flex chassis
Griffiths, Duncan wrote:
>
> I don't think the tuned flex works anywhere. ...
> ...Honda's grand experiment might work well for making street bikes more
> comfortable on rough pavement when not riding at the limit, but it does
> not make sense for true racing machines. Enough riders have tried and
> abandoned it to make that fairly clear.
> Duncan
As much as I revere Honda, I still think the extent of their 'grand
experiment' has/had a lot more to do with marketing and product cost
reduction than anything else. I suspect Suzuki is following suit.
I seem to recall earlier efforts with frames that flexed used some more
emotional appellations... like 'Widowmaker', Flex-Flyer', and
'Whispering Death'. Perhaps Norton's 'Garden Gate' frame was more of an
innovation than the Featherbed...
Marty
------------------------------
Date: Mon, 17 Aug 1998 15:03:38 -0700
From: GD
Subject: MC-Chassis Inertia Dyno Math Needed !
I have been working on my new
inertia dyno and now I am in need of
someone who can help me with the
math so that I can write the math
channel to figure the torque and
then the horsepower. I have found a
couple of web sites that talk about
what it takes but they are
converting the HP from metric
measurements and then converting
it. I would like to figure it in
english and avoid the conversion.
Any help would be greatly
appreciated.
Thanks
GD
------------------------------
Date: Mon, 17 Aug 1998 16:59:02 -0700
From: yhakim@m5.sprynet.com
Subject: RE: MC-Chassis tuned flex chassis
Well the lap record was set by Harada on his way to a championship, so the
Yahama couldn't have been too much of a slouch. And the article was actually
discussing tuned flex, so the NSR was a TF (from here on out I'll use TF for
tuned flex) bike. The two best examples I can give of TF functioning are:
The year escapes me now, but Rainey had a bike that he declared too stiff and
when cranked over would "skitter" across the bumps and he couldn't hold a
line. Also Superbikes went to smaller diameter fork tubes because they help
to absorb those lateral bumps. Along a similar vein Superbikes are running
16.5 inch rims and tires with bigger sidewalls to perform similar function.
Is un-dampened flexi-chassis and tire flex the best solution, no. It is,
however a solution that works. It does cause some problems of its own, but
obviously if it is being used than it must be worth it.
This current batch of TF is not at all akin to the flexi chassis of yore, or
loose SA bushings. The point of TUNED flex is that it will do something
predictable i.e. absorb bumps, at the limits of traction.
Now I am not saying that TF is a holy grail. Nobody has complained about the
Britten and people racing CBR9's usually resort to pre TF (stiffer) chassis.
However TF is also not a complete waste of time that needs to be killed on
sight. Now I'm sure part of it is marketing, but there is some substance.
Yousuf
On Mon, 17 Aug 1998, "Griffiths, Duncan" wrote:
>I don't think the tuned flex works anywhere. The longer you would be
>leaned over, the more undamped oscillations it can get itself into. I've
>found significant improvements in moving from the '91 TZ to a '93, which
>has a significantly stiffer chassis.
>
>The broken lap record may have been obliterated by a rigid bike that had
>an equivalent engine spec to the NSR. A TZM is not in the same league as
>an NSR.
>
>The 125's rely on corner speed high lean angle. The last thing they
>would want is to have the chassis do something uncontrolled at the limit.
> Honda's grand experiment might work well for making street bikes more
>comfortable on rough pavement when not riding at the limit, but it does
>not make sense for true racing machines. Enough riders have tried and
>abandoned it to make that fairly clear.
>Duncan
>====================
>
>From: yhakim@m5.sprynet.com
>Tuned flex chassis probably work at tracks where you spend a lot of
>time leaned way over. I believe a NSR250, with tuned flex, beat a lap
>record set by Harada (on the TZM250 at the time).
>Now having said all that I don't understand why I've never seen Honda
>try anything with the 125's. They rely on high speed, extreme lean
>angles more than most classes.
>
------------------------------
Date: Mon, 17 Aug 1998 20:33:00 -0400
From: camillieri@earthlink.net
Subject: MC-Chassis Stiff frames
I just unloaded my race bike and noticed that the bolt that secures
the SA pivot was hanging from its lock wire. The SA pivot shaft is
actually a 5/8 tube with 3/8 allen screws and hard washers on each
end. Somehow it had loosened without breaking the lock wire. It
was handling fine, in fact I grounded the primary case a few times
which I hadn't done before, so I guess the frame is stiff enough. The
shaft had started to come out, but was stopped by the brake lever.
Now I have to figure out how it loosened. Good thing it was a short
race.
Frank
Frank Camillieri
Chester, NH
------------------------------
Date: Mon, 17 Aug 1998 18:48:50 -0600
From: "Jim Schneider"
Subject: Re: MC-Chassis Stiff frames
Frank,
Assuming that the 3/8" allens on each end are both right hand threaded, then
somehow you got the safety wiring wrong in its routing. With a set up like
this, even the pivot tube couldn't turn, as it would be securely held on the
other end by the safety wiring there. So, it had to be the loose bolt that
turned and evidently you must have attached the wiring so that it could
loosen and turn.
Jim
Swiss
- -----Original Message-----
Subject: MC-Chassis Stiff frames
I just unloaded my race bike and noticed that the bolt that secures
the SA pivot was hanging from its lock wire. The SA pivot shaft is
actually a 5/8 tube with 3/8 allen screws and hard washers on each
end. Somehow it had loosened without breaking the lock wire. It
was handling fine, in fact I grounded the primary case a few times
which I hadn't done before, so I guess the frame is stiff enough. The
shaft had started to come out, but was stopped by the brake lever.
Now I have to figure out how it loosened. Good thing it was a short
race.
Frank
Frank Camillieri
Chester, NH
------------------------------
Date: Mon, 17 Aug 1998 19:22:40 -0600
From: "Jim Schneider"
Subject: Re: MC-Chassis Stiff frames
The Hawk 650 v-twin engine weighs closer to 135lbs without oil or carbs. I
know because I shipped one out and had to weigh it closely in order to get
it under the 150lb weight limit of UPS. However, when you look at some of
the Singles and what they weigh with the electric start, this isn't bad for
a v-twin. The electric start Rotax, Honda 650 and Yamaha 600 (I assume the
660 also) all weigh over the 100lb mark. Engines like the Husaberg single
and the Folan singles and twins are the lightweights of the 4-stroke market,
but they are all limited in production and have a well defined "nitch"
market. The Husaberg 500 and 600 versions were in the sub 60lb range and
the Folan v-twin is reputed to be about 85lbs.. I don't think that those
aircraft engines include a 5 or 6-speed transmission, but that really is
just a few extra lbs. anyway.
I don't know what Hawk engine that you are talking about, but the 650 is
about 40cu.in. and that works out to 3.4lb/cu.in. That is MUCH better than
the 7lb/cu.in that you figured??
Jim
Swiss
- -----Original Message-----
From: batwings@i-plus.net
To: mc-chassis-design@list.sirius.com
Date: Monday, August 17, 1998 7:52 AM
Subject: Re: MC-Chassis Stiff frames
>At 07:20 AM 8/17/98 -0400, you wrote:>
>>Honda tended to go overboard on those Hawks. It must have the heaviest
>>engine to displacement weight ratio ever produced. Years ago someone told
>>me they used zinc in their castings because the junk aluminum was porous.
>
>That motor weighed over 110 lbs, or over 7 lbs/cu in. Many aircraft motors
>weigh no more than ~2 lbs/cu in. But the castings if they had zinc in them
>had little, as they looked and machined exactly like all other aluminum
>castings in my experience. I think yer pal must have been de-rating the
>Japanese, who in reality have never been techno-challenged.
>
>Hoyt
>
------------------------------
Date: Mon, 17 Aug 1998 20:01:01 -0800
From: "Michael Moore"
Subject: Re: MC-Chassis Stiff frames
> I don't know what Hawk engine that you are talking about, but the
> 650 is about 40cu.in. and that works out to 3.4lb/cu.in. That is
> MUCH better than the 7lb/cu.in that you figured??
Hello Jim,
The CB77 SuperHawk. You know, the REAL one!
Cheers,
Michael
------------------------------
Date: Mon, 17 Aug 1998 18:52:32 -0700
From: Dick Brewster
Subject: MC-Chassis Hard Anodize
Frank Wrote
<< Hoyt,
That TZ spacer was probably hard coat anodized. It's only about
.002 thick but
super hard. It's something like what they use in grinding wheels.
I never thought
about having spacers hard coated and we have a lot of parts hard
anodized at
our shop. I think it's worth trying.
Regards,
Frank >>
Hard anodize is good for wear and corrosion protection under some
conditions. However, since it is only 0.002 inch or less thick,
think of it as the shell on a hard boiled egg. It gives you the
initial impression that you have a very stong stiff structure (as
long as you are loading the part in compression). Unfortunately,
as soon as you break through the shell, you have a mess.
Actually, my analogy isn't nearly strong enough, an egg shell
does add a lot of strength to ahard boiled egg.
Dick
------------------------------
Date: Mon, 17 Aug 1998 22:43:58 -0600
From: "Jim Schneider"
Subject: Re: MC-Chassis Stiff frames
Techno-history. Well, when I was in Alaska, the Japanese were buying up
every bit of metal that was for sale. Was told that they even bought stuff
that was left over from the Gold Rush Days!! They shipped them to the coast
in open railroad cars and then took the cars also. I guess (this was in the
early 70's) this became many of the Cars and Bikes of the late 70's early
80's. A little later than the SuperHawk. Which by the way, my brother had
one that I rode a time or two. I started out with a CL Scrambler. Long
time ago, but I think they were about the same weight as the 500 Triumphs.
Jim
Swiss
>
>The CB77 SuperHawk. You know, the REAL one!
>
>Cheers,
>Michael
------------------------------
End of MC-Chassis-Dgst V1 #729
******************************
MC-Chassis-Dgst Tuesday, August 18 1998 Volume 01 : Number 730
1. "Thacker, Heath HW" Subj: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
2. "Thacker, Heath HW" Subj: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
3. batwings@i-plus.net Subj: Re: MC-Chassis Hard Anodize
4. "D Hixon" Subj: Re: MC-Chassis Tyre Loading & Lean angle Clearance.
5. "Calvin Grandy" Subj: Re: MC-Chassis Hard Anodize
6. yhakim@m5.sprynet.com Subj: MC-Chassis bike racing sims
7. batwings@i-plus.net Subj: MC-Chassis Frank C's SA bolt
8. "Frank Camillieri" Subj: Re: MC-Chassis Frank C's SA bolt
9. geoff@pop.ihug.co.nz (Geoff Merryweather. ) Subj: Re: MC-Chassis Inertia Dyno Math Needed !
----------------------------------------------------------------------
Date: Tue, 18 Aug 1998 14:42:07 +1000
From: "Thacker, Heath HW"
Subject: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
> From: D Hixon[SMTP:fshixon@muskie.lerc.nasa.gov]
>
> About the GSX-R links: Dale Rathwell made them for the '88-'89's; I
> *think*
> Fox took that over, but I'm not sure on it. Supposedly they were the
> hot
> ticket.
>
Thanks for the information, Ray. When you say they were the "hot
ticket", did they have other advantages besides increasing ride height ?
Is this a better option than installing a ride height adjuster.
> Another '88-'89 tidbit: the Computrack guys told me that those frames
> were very close to perfect geometry out of the box.
>
Thanks Ray, your making me glad I decided to keep my '88. Sounds like
if I fit the new links or a ride height adjuster & then an 1100 engine,
I'll have a hot bike.
Thanks,
Heath.
------------------------------
Date: Tue, 18 Aug 1998 14:55:25 +1000
From: "Thacker, Heath HW"
Subject: RE: MC-Chassis Tyre Loading & Lean angle Clearance.
> From: Alan Lapp[SMTP:level_5_ltd@earthlink.net]
>
> They were notorious for poor damping. My recommendation is to send
> the
> forks to Race Tech or Traxxion Dynamics for revalving, polishing of
> the
> orfices, and a Gold Valve cartridge emulator setup.
>
New progressive springs helped a lot, so new valving should complete the
picture.
> For the rear, I'd suggest a Fox shock: reasonably priced and fully
> adjustable. This includes a ride height adjustment.
>
Unfortunately, I just installed a new Works Performance rear shock, (as
I thought my ground clearance problems related the the very poor stock
rear shock), and it doesn't have a ride height adjuster. Hopefully,
I'll be able to buy an aftermaket one, and get it to fit with the WP
shock ? Anyone know if you can get ride height adjusters by themselves
? Does this have an advantage over new linkages ?
> This is making the assumption that you've exhausted the possibilitites
> with
> the stock setup. One fork setup parameter which is often overlooked
> is
> fork oil height.
>
Whilst I have just done this for my dirt bike with great results, I
didn't even consider it for my road bike.
> By raising the fork oil level, the quantity of air (a
> compressable gas as opposed to the non-compressable oil) is reduced.
> This
> won't have any effect on initial travel, but will add a great deal of
> progressivity in the top half of the compression stroke. This may
> have the
> desired effect of increasing ground clearance since cornering force
> compresses the suspension.
>
Could be it, I'll have a look this weekend, (my girlfriend will also be
riding my GSXR on a pratice day).
But I feel like its dragging it ass more than the forks compressing,
under hard cornering.
Thanks everybody for your help,
Heath.
'88 GSXR750J
'95 YZ125G
------------------------------
Date: Tue, 18 Aug 1998 07:39:28
From: batwings@i-plus.net
Subject: Re: MC-Chassis Hard Anodize
At 06:52 PM 8/17/98 -0700, you wrote:
>Hard anodize is good for wear and corrosion protection under some
>conditions. However, since it is only 0.002 inch or less thick,
>think of it as the shell on a hard boiled egg.
If you want more thickness on your hard-anodize, leave it in the bath
longer. It can be built up to considerably greater than mentioned here.
BTW, I do use aluminum sometimes, but there's no savings in weight for
spacers and bushings, etc over steel, as for the same strain you need three
times as much Al. That's right: the greater weight of steel is in
proportion to the greater strength, so a spacer or whatever having the same
strength weighs about the same regardles of what it's constructed.
To the guy who wanted to give me all his steel spacers: I'll take em, but I
oughta warn you, I do also machine them thinner depending on application,
and occcasionally I'll bore out an axle too. One doesn't need as much in a
racer no matter what materials used. For street buikes, the fatty look does
add some reliability in fastening applications.
Hoyt
------------------------------
Date: Tue, 18 Aug 1998 11:44:06 -0400
From: "D Hixon"
Subject: Re: MC-Chassis Tyre Loading & Lean angle Clearance.
About the Rathwell links for the '88-'89 GSX-R750: apparently, the rear
suspension in stock form was *way* too progressive (read: initially very
soft, then instantly rock-hard), and hard to come off corners well with.
The illustrative story is when Kurt Hall switched from the Human Race Team
FZR1000 Yamaha to the Team Suzuki GSX-R, he was amazed at how badly it
handled coming out of corners (hard to put the power down). After TS put
on the Rathwell link, it was comparable to the FZR's handling.
A 7-11 GSX-R would be a *really* fun race bike -- I've been half-considering
tuning one down for the 102 hp class (try to get 102 hp *everywhere* in the
rev range).
BTW: the 750 front forks are also very good out of the box. Apparently
Race Tech doesn't even sell a Gold Valve for them; they're good as they
are.
Time to get the GS500 together...
Ray Hixon
------------------------------
Date: Tue, 18 Aug 1998 12:17:15 -0400
From: "Calvin Grandy"
Subject: Re: MC-Chassis Hard Anodize
This thread brings out a typical theme of rejection or acceptance of
materials based on comparisons with other materials, rather than a
materials suitability for the intended service application.
In this case we need to justify the compressive strength of an axle
spacer in order to minimize undesirable flexing of the complete
spindle assembly. Hoyt has offered a useful response, to use a
"good" material to it's greatest advantage. Steels' strength
advantage over aluminum allows smaller sections to achieve the same
result. Alas, It rusts if not protected, and does not look as
"racy".
Again in this example, The load on the spacer is really the clamp up
stress developed by the axle nut on the axle. The stain is in
pounds per inch per inch, or any equal. The axle sees inches per
inch elongation, the spacers see inches per inch reduction in length.
The wheel bearing distance piece, bearings and associated spacers
are all in line for this same load. I would venture that barrel
distortion of the long spacer between the bearings would be the week
link in compression. This is in the stiffness category (Young's
Modulus) Surface hardness should not have much effect on this
deformation. Although pre stressed skins could be investigated.
>From some early work on the rear wheel bearing spacers made from
steel,(XLCR1000) I find that the clamp up pressure from a large axle
bolt can over power typical spacers, i.e. greater tightening =
greater compression, so some reasonable torque figure for the axle
bolt is used. This resulting compressive loading is inside the
envelope of both aluminum and steel on a strength to weight basis.
There is another aspect that should not go ignored. If the there is
looseness any where in this set up, dynamic loads will cause the
parts to "work", and wear will show on the soft parts. Hard parts
(hard anodized or steel) will survive better under this undesirable
condition. Remember that it is the self protective conversion of
aluminum to aluminum oxide that keeps this metal from "rusting" away.
The Al2O3 (alu. oxide) that forms on the surface when broken away by
distortion of the surface, provides the hard abrasive required to
self destruct the under surface.
There is a corollary termed "fretting corrosion" for any loaded
assemblies.
The problem is not the parts, but rather insufficient clamp up.
Tighten the nut!
The difficulty of getting good clamp up on a column of individual
parts is not trivial. There is difficulty with the spacers on the
arbor of my horizontal milling machine, and these items are hardened
and ground. A bit of swarf will spoil everything. There is a reason
to the cotter on axle nuts. But when is the last time you had a head
bolt work loose? ( no comments from the big singles;-)
I am really wishing that I could run through all the numbers and
produce an algorithm for the exchange of aluminum and steel spacers,
but I am away from my library, and lunch is half over.
Regards
Calvin Grandy
- ----------
> From: batwings@i-plus.net
> To: mc-chassis-design@list.sirius.com
> Subject: Re: MC-Chassis Hard Anodize
> Date: Tuesday, August 18, 1998 3:39 AM
>
> At 06:52 PM 8/17/98 -0700, you wrote:
> >Hard anodize is good for wear and corrosion protection under some
> >conditions. However, since it is only 0.002 inch or less thick,
> >think of it as the shell on a hard boiled egg.
>
> If you want more thickness on your hard-anodize, leave it in the
bath
> longer. It can be built up to considerably greater than mentioned
here.
>
> BTW, I do use aluminum sometimes, but there's no savings in weight
for
> spacers and bushings, etc over steel, as for the same strain you
need three
> times as much Al. That's right: the greater weight of steel is in
> proportion to the greater strength, so a spacer or whatever having
the same
> strength weighs about the same regardles of what it's constructed.
>
> To the guy who wanted to give me all his steel spacers: I'll take
em, but I
> oughta warn you, I do also machine them thinner depending on
application,
> and occcasionally I'll bore out an axle too. One doesn't need as
much in a
> racer no matter what materials used. For street buikes, the fatty
look does
> add some reliability in fastening applications.
>
> Hoyt
>
------------------------------
Date: Tue, 18 Aug 1998 09:47:50 -0700
From: yhakim@m5.sprynet.com
Subject: MC-Chassis bike racing sims
Not entirely list related, but in addition to the Castrol Honda
Superbike Racing that has already shipped, Virgin interactive is
producing a superbike racing game that looks to be sanctioned by
official SBK bodies (the teaser site uses the official logo).
------------------------------
Date: Tue, 18 Aug 1998 13:05:22
From: batwings@i-plus.net
Subject: MC-Chassis Frank C's SA bolt
Could be one of several causes. They'll loosen up sometimes w/o even
rotating, from fretting wear in threads. CZ used a pivot tube and cap
screws on the ends and they loosened constantly. The problem may be
insufficient preload, in which case Frank should shorten the 5/8" pivot
tube a thread or two, to prevent the cap screws bottoming before everything
is thoroughly tight. The washers carrying the load to the frame may be
flexing too, hardened or not, as in this application they must span the
diff in dia between the cap screw and pivot tube ODs.
Sometimes the problem is insufficient strain in the whole asm, as things
settle down in service, esp if newly asm'd. The idea is to have the
over-all strain be bigger than the entire settling-down process, so when
paint for ex does fret away, there is still preload. This is hard to do
with the cap-screws arrangement above, as most of the strain appears in the
screws and they reach torque before stretching enough needed as above. If
the strain is to be distributed over the entire width in this arrangement,
the tube wall must be .707 times the root radius of the bolt threads for
things to be evenly stretched. You are also limited to the strain the cap
screws can take.
A better arrangement would be to extend the tube and fine-thread each end
and then use two nuts and larger thick washers. Now, your washers span
nothing, your strain is evenly spread throughout the width (and for 8" nose
and .25% strain, that is .020" total), and your total preload can be much
higher. Of course depending on your specific construction details, this may
not work out. Enjoy.
Best wishes,
Hoyt
------------------------------
Date: Tue, 18 Aug 1998 16:03:32 -0400
From: "Frank Camillieri"
Subject: Re: MC-Chassis Frank C's SA bolt
> A better arrangement would be to extend the tube and fine-thread each end
> and then use two nuts and larger thick washers.
I think you're right about the pivot bolt. I'll make a headed bolt with a fine thread
and large nut. I'll be able to tighten it up much better.
Thanks,
Frank
Frank Camillieri
Chester, NH
------------------------------
Date: Tue, 18 Aug 1998 20:34:08 GMT
From: geoff@pop.ihug.co.nz (Geoff Merryweather. )
Subject: Re: MC-Chassis Inertia Dyno Math Needed !
There is a link to a kart web page that has a DIY dyno section on my
homepage. Follow the dyno links. My dyno is sort of running (have
computer bug to sort out), and I have some photos I have yet to
develop
I also have a spreadsheet to calculate inertia approximately. E-mail
me if you want it...
Geoff
On Mon, 17 Aug 1998 15:03:38 -0700, you wrote:
> I have been working on my new
>inertia dyno and now I am in need of
>someone who can help me with the
>math so that I can write the math
>channel to figure the torque and
>then the horsepower. I have found a
>couple of web sites that talk about
>what it takes but they are
>converting the HP from metric
>measurements and then converting
>it. I would like to figure it in
>english and avoid the conversion.
>Any help would be greatly
>appreciated.
>
>Thanks
>
>GD
- --
------------------------------
End of MC-Chassis-Dgst V1 #730
******************************